Rare groove is the stuff that killer record collections are built on: obscure R&B, jazzy funk, and funky soul plucked from the deepest and dustiest of crates. Of course, not all listeners have the time, patience, or cashflow to go musical spelunking for old-skool gems. With that in mind, Rhino's superb four-disc box set, WHAT IT IS! FUNKY SOUL AND RARE GROOVES: 1967-1977, takes care of the hard part and offers 91 tracks of deep, sweaty funk from the genre's heyday.

While a number of the artists will be familiar to the average fan (the Commodores, Rufus Thomas, Labelle, Little Richard, among others), many more won't (Cornell Dupree, Cold Grits, Black Heat, Society's Bag, United 8, etc.). Of course, obscurity is the name of the game here: It's not hard to find a DJ spinning "Brick House," but Little Sister's "Stanga"--included here--is a different bag all together. Wallflowers beware, and "all the squares, go home